Improvement in saw-sharpening machines



P. D. BURGHER.

sAWsHARPEN1NG MACHINE.

X in which the grinding-shaft b revolves.

UTTED STATES IPATElif-vY FFICE;

PETER D.ABURGHER, OFDEEP CREEK, VIRGINIA.l

IMPROVEMENT IN SAW-SHARPENING MACHINES.

Specification forming' part of Letters Patent No. 184,832, dated November 28, 1876; application filed April 27, 1876.

I To all whom it may concern Be it known that I, PETER D. BURGHER, of Deep Creek, in the county of Norfolk-and State of Virginia, have invented certain new and useful Improvements in Machines for ra machine of the above class more especially adapted to the sharpening of circular saws, and to the means employed to center the saws,

and hold the same in various angular posi-- tions during the sharpening operation, which consists, broadly, in bringing the saws in contact with a revolving grinding-disk, as hereinafter described.

My invention relates, secondly, to means whereby the said machine is adapted to the sharpening of straight or gang saws of various widths, and of various descriptions of teeth, the devices employed being adjustable to suit the angle of the teeth, as in the case of the mechanism used in the manipulation of circular saws, above referred to.

In the description of my invention which follows, due reference must be hadrto the accompanying drawing, forming a part of this specification, and in which- Figure l is a side viewv of the machine, partly in section; Fig. 2, a front view of the same; Fig. 3, a plan of the invention, and

j parts in all the figures.

A is a stand, provided with the bearings a, The stand A is secured to the top of the frame c,

' the means of connection being a bolt, d, tted to pass loosely through a curved slot, e, in the stand` into the frame c, to which it is fastened.

By this mode of attachment the stand A,

i with the shaft, grinding-disks g, and other attachments hereinafter referred to, may be moved independently of the frame, and made to assume various positions in the saine plane with reference to the said frame and the hold ing and other devices, hereinafter described.

B is a track, the inner end of whichl is piv-l vby a stop, p, the' position of which is regulated through the medium of a screw, p. D D are standards projecting from the upper side of the carriage 0, and serving to support the saw-swing E, suspended from the upper ends thereof.

The saw-swing is held at any desired angle of inclination by means of a set-screw passing through a slot in one of the standards.

The means' for centering and holding thev Y circular saw to the saw-swing consist of a cylindrical stud, F, projecting from the sawswing and two conical blocks, G G', which fit over the stud, and are held thereto by a bolt, q, and washer q.

The manner of their application is as follows: ,The saw is laid upon the block G, vand the block G inserted through the central aperture in the saw, into the block G, and over the cylindricalstud F. The bolt q and washer q are then applied and a slight tension placed thereupon. Y l It will be seen that by the use of these devices, saws with various-sized spindle-apertures can be centered without alteration in the existing mechanism'.

The object in making the Obliquity ot' the saw variable by means of the saw-swing,fas described, is to giveany desired angle of 'cutting-edge to the teeth in grinding, and thereby adapt them for any description ofl work".

-The parts of my inventionv used in connecfollowing-described mechanism: A shaft, H, is adapted to partially revolve in bearings situated in the frame c, and is provided with the arms I, which may be placed at any angle with reference to each other, and secured thereat by setlscrews. 1I' I' are heads constructed to be moved to and fastened at any part of the arms'I, and are fitted with the vibratory plates I". The plates I" have projections s, which serve as bearings or holders for the extensible rods K. K' K' are rollers or pulleys, upon which the straight saw rests, and is moved longitudinally in the sharpen ing operation.

It will be seen that the` rods K may be' placed in such relative positions as to give to the saw laid upon the rollers K' an angular or inclined position Awith reference to the shaft H, and thereby cause an oblique or angular edge to be ground on theA saw-teeth when they are brought into contact with the 'grinding-disks g, and that by their adjustability in other respects, by reason of the movable arms to which they are connected, teeth C of any desired shape may be ground.

L is a slotted curved bar, fitted for attach` [ment to the arm i at any portion of its length, j and provided with adjustable stops L', which y regulate the transverse movement of straight saws in the sharpening operation, hereinafter l described. f

Parts of the machine not yet alluded to will be described and their uses set forth in` the description of the operations of sharpening circular and straight sawswhich follows:

i The circular saw having beensecured to the saw-swing, as hereinbefore explained, the

' track B is moved 'to a position that will bring the cutting-edge of the saw-teeth parallel with the back or at side of the` emery-wheel, and thesaw inclined laterally to give the necessary angle of cutting-edge.

The inner end of the track is then elevated orrdepressed by means of the movable pivot on the thumbscrew 7c, in order that the saw may tend toward the center of the grinding-disk, or to a point above or below it, as may be desired.

The stop p is now adjusted to regulate the l forward motionof the saw or the length of the teeth.

A The several movable parts of the machine ji Yhaving thus beenvadjusted and secured in their respective places, the emery-wheels are put in revolution `and the saw moved toward the one to be used by meansof the lever m. One tooth of the saw is thus brought into After the completion of the tooth the saw is withdrawn and partially revolved, and the next toothmoved into position, the stop p regulating the forward movement in each CaSe.

The entire number of teeth having been ground, their points are, by another complete revolution of the saw, successively brought into contact with the beveled edge of the wheeli'fto grind them to a common length, or their ends to a uniform distance from the cen- 'ter rof the saw..

. During this final operation the gage t, which is hinged or pivoted to the arm N', and adjusted by means of a set-screw, N", is brought into requisition, and secured in such manner as to give, when the teeth are successively brought against the gage, the common required angle to the point of the teeth.

The operation of sharpening straight or gang saws by means of my improved machine is as follows: Thel distance over the rollers or pulleys K' being arranged to suit the width of the saw by means of the extensible rods K, the angle of the saw or its deviation from a horizontal line is then determined upon, andthe arms I secured or set to suit the depth when brought into contact with the `grinding-disk, and suicient backward movement to admit of the saw being withdrawn entirely from the disk to allow of the feed motion. The grinding-disks are now put in revolution, and each tooth of the saw brought successively into contact therewith and ground. The backs of the teeth are subjected to the same method of grinding, in connection with the cross-piece N and gage t, as those of the circular saw before mentioned.

M is a plate attached adjustably to an arm pivoted to the stand A, to be used witha round or tlat edged grinding-disk, to cut out the spaces between the teeth, or in other manipulations of saws not forming a part of the regular sharpening operation.

Having thus described my invention, what I claim as new, and wish to secure by Letters Patent of the United States, is-

l. The carriage C and saw-swing E and its attachment, adapted to be moved by the 1ever m, in combination with the stop p and screw p', substantially as and for the purpose bratory plates I", and extensible rods K, subto the said stand, and adapted for use in constanti'ally as shown. nection with a grinding-disk, substantially as 6. The extensible rods K, in combination and for the purpose set forth.

with the pulleys or rollers K', substantially as In testimony whereof I have hereunto subdescribed. Y scribed my name this 10th day of April, in th 7. In combination with the arm z', the curved year of our Lord 1876.

bar L, provided with the adjustablel stops L',

substantially as and for the purpose specii PETER D. BURGHER. fied. Witnesses 8. In combination with the stand A, the J. L. RAPES,

plate M, attached adjustably to an arm pivoted R. D. PARROTT. 

